1. Field of the Invention
The present invention relates to a lever type connector in which male and female connector housings can be connected or disconnected by rotating a lever with only a small operating force.
2. Description of the Related Art
Conventionally, for a connector which requires a large connecting force such as a multi-terminal connector, a lever type connector having a lever for assisting the connecting force has been utilized. In the lever type connector, a lever having a cam groove on one connector housing (for example, a male connector housing) is rotatably provided, and a cam pin to be guided by the cam groove is provided on another connector housing (for example, a female connector housing). The cam pin is inserted into an entry gate of the cam groove at an initial stage of connecting both connector housings where a lever is positioned at a start position. Next, the cam pin is guided into the can groove by rotating the lever, and then the both housings are firmly connected with a small operating force of the lever by utilizing the principle of leverage.
FIG. 1 and FIG. 2 show one embodiment of a conventional lever type connector described in Japanese Patent Application Laid Open No. 2002-216894. FIG. 1 shows a state before a cam pin is inserted into a cam groove. FIG. 2 shows a state in which the cam pin is inserted into the cam groove and fixed.
This lever type connector has a pair of male and female connector housings 910 and 950 to be connected with each other. In each terminal cavity of the connector housings 910 and 950, terminals (not shown in figures) are accommodated. The arch-shaped lever 930 for connecting operation is attached to the connector housing 910 at outer side surface of one connector housing. An axial hole 932 and the cam groove 940 are formed on each base end of the lever 930. A knob 949 is formed on a center of the lever 930.
Each of the cam grooves 940 extends in a prescribed angle range around the axial hole 932 (center of the angle). A distance from the axial hole 932 to the cam groove 940 decreases gradually from an entry gate 941 towards an opposite end. A pin 912, to which the axial hole 932 is rotatably coupled, is provided on each side of the connector housing 910. The lever 930 is rotatably attached by coupling the pins 912 with the axial holes 932 respectively. As a result, the lever 930 will be rotated around the pin 912 (center of the rotation) between start and end positions.
The cam pin 955 to be guided by the cam groove 940 of the lever 930 is provided on each side of the connector housing 950. When a pair of the connector housings 910 and 950 is to be connected, the cam pin 955 is positioned near the entry gate 941 of the cam groove 940 of the lever 930 positioned at the start position. FIG. 21 shows a state in which the cam pin 940 has been slightly entered into the cam grooves 940 through the entry gate 941.
A notch 942 is provided on an inner edge of the respective cam groove 940 near the entry gate 941 for temporarily holding the cam pin 955 which has entered through the entry gate 941. A pawl 943 is provided on an entry side of the respective notch 942 for holding the cam pin 955. Therefore, the cam pins 955 are held by the notches 942 respectively in an initial stage of connecting and then the connector housings are temporarily locked for preventing disconnecting.
When the pair of the connector housings 910, 950 is loosely connected with the lever 930 positioned at the start position, the respective cam pin 955 is inserted into the entry gate 941 of the respective cam groove 940 and held by the respective notches 942. And then, the lever 930 is rotated toward the end position by grabbing the knob 949. The respective cam pin 955 is entered into the cam groove 940 deeply. The connector housings 910, 950 are connected by the cam structure between the cam groove 940 and the cam pin 955.
On the contrary, the lever 930 is rotated in an opposite direction when the both connector housings 910, 950 are to be disconnected. The both connector housings 910, 950 will be disconnected by the principle of leverage applied between the cam groove 940 and the cam pin 955.
In the above-described lever type connector, it is needed to fit positions of the respective entry gate 941 and the respective cam pin 955 when the both connector housings 910, 950 are to be connected temporarily. However, if connecting potions of the both connector housings 910, 950 have much looseness, much work for fitting the positions must be needed and then connecting workability must be reduced.